An integrated test device and method for short-term and long-term aging of stirred airflow type asphalt

Abstract

The present invention relates to a stirring airflow type asphalt short-term and long-term aging integrated test device and test method. The test device and method of the present invention can realize short-term and long-term aging simulation in an oxygen environment, and can carry out asphalt aging simulation tests in an ultraviolet environment and the coupling effects of ultraviolet rays, high temperature, and oxygen. During the simulation process, the temperature, oxygen concentration, and ultraviolet irradiation intensity can be adjusted according to test needs. The unique structural setting of the device can make the airflow contact with the sample more fully during stirring, and the simulated aging effect has a higher degree of fit with the aging process during asphalt production and preparation, which solves the technical problems that existing equipment cannot carry out short-term and long-term aging tests on the same equipment, and the current test equipment has a single simulated environment and limited simulation degree. The device of the present application has a simple structure, is easy to operate, has rich functions, and is easy to clean and move. At the same time, it solves the problems of complex structure, difficult cleaning, single function, and low simulation degree of existing equipment.

Description

Technical Field

[0001] The invention relates to the field of equipment for testing asphalt indexes, and in particular to a stirring airflow type asphalt short-term and long-term aging integrated testing device and a testing method. Background Art

[0002] The aging stages of asphalt used in paving projects include short-term aging and long-term aging. Short-term aging mainly occurs during the high-temperature production, storage and construction of asphalt, while long-term aging occurs during the long-term service of asphalt pavement and its contact with external sunlight (ultraviolet rays), oxygen, high temperature and other environments, resulting in irreversible physical and chemical changes, namely asphalt aging. At present, the laboratory simulation test and performance verification and evaluation methods for the long-term aging of asphalt and the test environment conditions that can be simulated are relatively simple, and the requirements for the materials and test conditions of the test instruments are extremely strict, and there are great safety risks in operation.

[0003] The existing asphalt aging test equipment cannot perform both short-term aging and long-term aging tests on the same device, and the existing test equipment also has problems such as complex structure, difficult cleaning, single function, and low test simulation level. Summary of the invention

[0004] In view of the above problems, the present application proposes a stirred airflow type asphalt integrated short-term and long-term aging test device, which solves the technical problems that the existing equipment cannot perform both short-term aging and long-term aging tests on the same device, and the simulation environment is single and the simulation degree is limited; the device of the present application has a simple structure, is easy to operate and has rich functions, and is easy to clean and move; it solves the problems of the existing test equipment with complex structure and difficult cleaning, single function, and low test simulation degree.

[0005] A stirring airflow type asphalt short-term and long-term aging integrated testing device comprises a first cylinder body and a second cylinder body;

[0006] The first cylinder is used to generate high-temperature gas;

[0007] A test chamber, an ultraviolet lamp and a stirrer are arranged inside the second cylinder; a motor for driving the stirrer is arranged outside the second cylinder; the stirrer is used to mix the test sample inside the test chamber;

[0008] A temperature sensor is provided in the test chamber; the temperature inside the test chamber can be monitored and controlled in real time through the temperature sensor;

[0009] The first cylinder provides high-temperature gas to the space between the second cylinder and the test chamber through the first fan; this part of the high-temperature gas is used to maintain the external environment temperature of the test chamber;

[0010] The first cylinder provides high-temperature gas to the interior of the test chamber through the second blower. This part of the high-temperature gas directly participates in the test in the test chamber;

[0011] The test chamber is provided with an air inlet pipe, an air outlet pipe, a feed pipe and a discharge pipe; the second fan provides high-temperature gas to the inside of the test chamber through the air inlet pipe.

[0012] Based on the above scheme, the agitator includes a hollow shaft and stirring teeth; the stirring teeth are evenly threadedly connected to the outer wall of the hollow shaft; the hollow shaft is hollow inside and has one end open and the other end closed, and the closed end is close to the motor; the stirring teeth are hollow inside and connected to the interior of the hollow shaft, and the first cylinder provides high-temperature gas to the hollow shaft through the third fan.

[0013] Based on the above solution, the end of the stirring tooth away from the hollow shaft is in a flat bell-mouth shape.

[0014] Based on the above solution, the distance between the end of the stirring tooth away from the hollow shaft and the inner wall of the test chamber is 1-2 mm.

[0015] This setting allows the high-temperature gas to act directly on the sample, and the high-temperature gas and the sample are in more direct contact while stirring; in order to increase the contact area between the high-temperature gas and the sample, the mouth of the stirring tooth is set to a flat bell-shaped shape, and this setting can also more effectively spread the sample in the test chamber; the stirring tooth is threadedly connected to the hollow shaft and can be disassembled after the test for easy cleaning;

[0016] Based on the above solution, the test chamber and the stirring teeth are made of quartz glass.

[0017] Based on the above scheme, the two ends of the test chamber are open and are respectively connected with fixed heads in a detachable manner; the temperature sensor is arranged on the inner wall close to the motor side. This design method can remove the test chamber and the agitator after the test, and the test chamber and the agitator can be easily cleaned after disassembly.

[0018] Based on the above scheme, the outlet pipe is connected to a condenser. The function of the condenser is to lower the temperature of the gas discharged from the outlet pipe and condense the volatiles in the asphalt sample carried by the high-temperature gas in the condenser. The weight lost by the test sample is obtained by weighing the weight of the condenser before and after the test.

[0019] On the basis of the above scheme, the first cylinder is provided with a fan, a first filter layer, a U-shaped heating tube and a second filter layer in sequence along the gas flow direction; the fan is fixed on the wall of the first cylinder. The first filter layer and the second filter layer can provide clean high-temperature gas to the test chamber.

[0020] An integrated test method for short-term and long-term aging of stirred airflow type asphalt is as follows:

[0021] (1) opening the U-shaped heating tube in the first cylinder, and producing high-temperature gas, which is respectively passed through the first fan, the second fan, and the third fan, to preheat the space between the second cylinder and the test chamber, the test chamber (3), and the hollow shaft;

[0022] (2) A temperature sensor is installed in the test chamber to monitor the internal temperature at any time. After the preheating is uniform, the sample is added into the test chamber through the feeding pipe, and the stirrer is turned on to simulate the short-term aging state;

[0023] (3) After step (2) is completed, some samples are taken out from the feeding tube for testing of short-term aging experiments, and the remaining samples continue to undergo ultraviolet high-temperature long-term aging simulation in the test chamber. The ultraviolet lamp is turned on, and the ultraviolet irradiance, temperature, oxygen and time are controlled to perform ultraviolet high-temperature long-term aging simulation. After the simulation is completed, the samples are taken out from the feeding tube for testing.

[0024] The specific test requirements for short-term aging can be found in: Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering JTGE20-2011, which will not be repeated here.

[0025] The present invention has the following advantages: the present invention uses the first cylinder as the source of high-temperature gas, and uses three fans to provide high-temperature gas to the second cylinder and the test chamber, which can not only reduce the risk of use but also achieve more uniform contact between the high-temperature gas and the sample; the present device solves the problem that the existing equipment cannot perform both short-term aging and ultraviolet long-term aging tests on the same device; at the same time, it can provide ultraviolet conditions and ultraviolet rays and high temperature, oxygen multi-environment coupling effects to simulate asphalt aging simulation tests. In addition to the above advantages, the equipment of the present invention does not need to open the test chamber when placing and removing samples, which is more convenient and safer. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 : A schematic diagram of the structure of the test device of the present invention;

[0028] Figure 2 : A schematic diagram of the structure of the test chamber in the test device of the present invention;

[0029] Figure 3 : The present invention Figure 2 A schematic diagram of the enlarged structure of part A;

[0030] Figure 4 : A schematic diagram of the main viewing angle structure of the stirring teeth in the test device of the present invention;

[0031] Figure 5 : Schematic diagram of the structure of the stirring teeth in the test device of the present invention from a top view. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0033] Embodiment 1:

[0034] like Figure 1 and Figure 2 As shown,

[0035] A stirring airflow type asphalt short-term and long-term aging integrated testing device comprises a first cylinder body 1 and a second cylinder body 2;

[0036] The first cylinder 1 is used to generate high-temperature gas and transport the high-temperature gas to the second cylinder 2 through a fan;

[0037] A test chamber 3, an ultraviolet lamp 6 and a stirrer 5 are arranged inside the second cylinder 2; a motor 4 for driving the stirrer 5 is arranged outside the second cylinder 2; the stirrer 5 is used to mix the test sample inside the test chamber 3;

[0038] A temperature sensor 23 is provided in the test chamber 3;

[0039] The first cylinder 1 provides high-temperature gas to the space inside the second cylinder 2 and outside the test chamber 3 through the first fan 13 ; the first cylinder 1 provides high-temperature gas to the inside of the test chamber 3 through the second fan 14 .

[0040] like Figure 2 As shown, the test chamber 3 is provided with an air inlet pipe 31 , an air outlet pipe 32 , a feed pipe 33 and a discharge pipe 34 ; the second fan 14 provides high-temperature gas to the inside of the test chamber 3 through the air inlet pipe 31 .

[0041] like Figure 3As shown, the agitator 5 includes a hollow shaft 51 and a stirring tooth 52; the stirring tooth 52 is evenly threadedly connected to the outer wall of the hollow shaft 51; the hollow shaft 51 is hollow inside and has one end open and the other end closed, and the closed end is close to the motor 4; the stirring tooth 52 is hollow inside and connected to the inside of the hollow shaft 51, and the first cylinder 1 provides high-temperature gas to the hollow shaft 51 through the third fan 15.

[0042] like Figure 4 and Figure 5 As shown, as a preferred solution, the end of the stirring tooth 52 away from the hollow shaft 51 is flat and trumpet-shaped, and the wide side is parallel to the axis of the hollow shaft 51. When the hollow shaft 51 rotates, the wide mouth of the stirring tooth 52 can increase the contact area with the asphalt sample, thereby increasing the contact between the high-temperature gas and the asphalt.

[0043] Preferably, the distance between the end of the stirring tooth 52 away from the hollow shaft 51 and the inner wall of the test chamber 3 is 0.5 mm-2 mm.

[0044] Preferably, the test chamber 3 and the stirring teeth 52 are made of quartz glass, and the hollow shaft can be made of corrosion-resistant stainless steel or corrosion-resistant ceramic.

[0045] Preferably, both ends of the test chamber 3 are open and are respectively connected with fixing heads 35 in a detachable manner; the temperature sensor 23 is arranged on the inner wall of the side close to the motor 4 .

[0046] The outlet pipe 32 is connected to a condenser 7. The function of the condenser 7 is to reduce the temperature of the gas discharged from the outlet pipe 32, and at the same time condense and intercept the volatiles in the asphalt sample carried by the high-temperature gas in the condenser 7. After the simulation is completed, the weight of the condenser before and after the test is weighed to obtain the weight loss of the test sample.

[0047] The first cylinder 1 serves as a source of high-temperature gas. In order to provide clean high-temperature gas, the first cylinder 1 is provided with a fan 1-1, a first filter layer 1-2, a U-shaped heating tube 8 and a second filter layer 1-3 in sequence along the gas flow direction; the fan 1-1 is fixed on the wall of the first cylinder 1.

[0048] In order to increase the heat preservation effect of the first cylinder body 1 and the second cylinder body 2, a heat preservation layer can be added on the outer wall thereof.

[0049] Example 2

[0050] The method for testing the short-term aging simulation of asphalt using the test device in Example 1 is as follows:

[0051] (1) The U-shaped heating tube 8 in the first cylinder 1 is turned on, and the high-temperature gas produced by the first cylinder is preheated to 163° C. by passing through the first fan 13, the second fan 14, and the third fan 15 to the space between the second cylinder 2 and the test chamber 3, the inside of the test chamber 3, and the inside of the hollow shaft 51;

[0052] (2) The temperature sensor 23 installed in the test chamber 3 monitors the internal temperature at any time. After the preheating is uniform, the sample is added into the test chamber 3 through the feed pipe 33, and then the feed pipe 33 is closed; the agitator 5 is turned on to simulate the short-term aging state. The specific temperature and time settings refer to: Highway Engineering Asphalt and Asphalt Mixture Test Procedure JTG E20-2011, which will not be repeated here.

[0053] The gas used in the test can be air or oxygen, preferably pure oxygen.

[0054] Example 3

[0055] The method for testing the ultraviolet long-term aging experiment of asphalt using the test device of Example 1 is as follows:

[0056] (1) After the short-term aging experiment of Example 2 is completed, part of the sample is taken out from the material taking pipe 34 for testing the short-term aging experiment, and the remaining sample continues to be subjected to ultraviolet high temperature long-term aging simulation in the test chamber 5;

[0057] (2) Turn on the UV lamp 6 and keep the average intensity of UV rays irradiating the asphalt surface at about 1200

[0058] μW / cm 2 In the UV test chamber, the asphalt is exposed to UV rays at 60°C for 9-14 days; the specific UV irradiance, temperature, oxygen and time can also be adjusted according to actual needs;

[0059] (3) After the simulation is completed, the sample is taken out from the material taking pipe 34 for subsequent asphalt ultraviolet long-term aging residue technical index testing and anti-aging performance evaluation.

[0060] The stirring airflow type asphalt short-term and long-term aging integrated test device of the present invention can provide short-term aging and long-term aging simulation conditions under an oxygen environment; it can also provide ultraviolet conditions and coupled simulation test conditions under ultraviolet, high temperature and oxygen environments; during the simulation process, factors such as temperature, oxygen concentration and ultraviolet irradiation intensity can be adjusted according to the needs of the simulation conditions. The unique structural setting of the device can make the airflow contact with the sample more fully during stirring.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A stirring airflow type asphalt short-term and long-term aging integrated test device, characterized by: It comprises a first cylinder body (1) and a second cylinder body (2); The first cylinder (1) is used to generate high-temperature gas; A test chamber (3), an ultraviolet lamp (6) and a stirrer (5) are arranged inside the second cylinder (2); a motor (4) for driving the stirrer (5) is arranged outside the second cylinder (2); the stirrer (5) is used to mix the test sample inside the test chamber (3); A temperature sensor (23) is arranged in the test chamber (3); The first cylinder (1) provides high-temperature gas to the space inside the second cylinder (2) and outside the test chamber (3) through the first fan (13); the first cylinder (1) provides high-temperature gas to the inside of the test chamber (3) through the second fan (14); The test chamber (3) is provided with an air inlet pipe (31), an air outlet pipe (32), a feed pipe (33) and a discharge pipe (34); the second fan (14) provides high-temperature gas to the inside of the test chamber (3) through the air inlet pipe (31); The first cylinder (1) is provided with a fan (1-1), a first filter layer (1-2), a U-shaped heating tube (8) and a second filter layer (1-3) in sequence along the gas flow direction; the fan (1-1) is fixed on the wall of the first cylinder (1).

2. The stirring airflow type asphalt short-term and long-term aging integrated testing device according to claim 1 is characterized by: The stirrer (5) comprises a hollow shaft (51) and stirring teeth (52); the stirring teeth (52) are evenly threadedly connected to the outer wall of the hollow shaft (51); the hollow shaft (51) is hollow inside and has one end open and the other end closed, and the closed end is close to the motor (4); the stirring teeth (52) are hollow inside and communicate with the inside of the hollow shaft (51); and the first cylinder (1) provides high-temperature gas to the hollow shaft (51) through a third fan (15).

3. The stirring airflow type asphalt short-term and long-term aging integrated testing device according to claim 2 is characterized by: The end of the stirring tooth (52) away from the hollow shaft (51) is in a flat bell-mouth shape, and the wide side is parallel to the axis of the hollow shaft (51).

4. The stirring airflow type asphalt short-term and long-term aging integrated testing device according to claim 2 is characterized in that: The distance between the end of the stirring tooth (52) away from the hollow shaft (51) and the inner wall of the test chamber (3) is 1-2 mm.

5. The stirring airflow type asphalt short-term and long-term aging integrated testing device according to claim 2 is characterized in that: The test chamber (3) and the stirring teeth (52) are made of quartz glass.

6. The stirring airflow type asphalt short-term and long-term aging integrated testing device according to claim 1 is characterized by: The test chamber (3) is open at both ends and is respectively connected with a fixing head (35) in a detachable manner; the temperature sensor (23) is arranged on the inner wall of a side close to the motor (4).

7. The stirring airflow type asphalt short-term and long-term aging integrated testing device according to claim 1 is characterized by: The air outlet pipe (32) is connected to a condenser (7).

8. An integrated test method for short-term and long-term aging of stirred airflow type asphalt, characterized in that: Use the test device according to any one of claims 1 to 7.

9. The method for integrated short-term and long-term aging testing of stirred airflow type asphalt according to claim 8, characterized in that: The specific method is as follows: (1) opening the U-shaped heating tube (8) in the first cylinder (1), and producing high-temperature gas to preheat the space between the second cylinder (2) and the test chamber (3), the inside of the test chamber (3), and the inside of the hollow shaft (51) through the first fan (13), the second fan (14), and the third fan (15); (2) A temperature sensor (23) is arranged in the test chamber (3) to monitor the internal temperature at any time. After the preheating is uniform, the sample is added into the test chamber (3) through the feeding pipe (33), and the stirrer (5) is turned on to simulate the short-term aging state; (3) After step (2) is completed, part of the samples are taken out from the feeding tube (34) for testing of the short-term aging experiment, and the remaining samples continue to be subjected to ultraviolet high-temperature long-term aging simulation in the test chamber (3). The ultraviolet lamp (6) is turned on, and the ultraviolet irradiance, temperature, oxygen and time are controlled to perform ultraviolet high-temperature long-term aging simulation. After the simulation is completed, the samples are taken out from the feeding tube (34) for testing.

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